1. Field of the invention
The present invention relates to a rack or carrier for cylindrically shaped heavy objects. Specifically, the invention relates to a portable carrier adapted to prevent the sliding and rolling of a heavy object such as a coil positioned horizontally during transportation on the flatbed of a truck or other vehicle.
2. Description of Related Art
In the field of transportation of heavy cylindrical objects such as large industrial sized coils of stock material, it is important to prevent the rolling or shifting of the object to prevent hazardous conditions that pose injury to workers and property. Coils or rolls of stock material, such as sheets of aluminum, steel, mill-rolls, belting, or the like, are frequently transported from a point of origin, such as the manufacturer, to their destination, such as a buyer, on the top of the flatbed of a truck or other vehicle.
These coils can weigh as much as 15 to 25 thousand pounds, the length of the coil may vary up to 4 feet, and the diameter is usually approximately four feet. Typically, these coils are loaded onto tractor trailers, such as a flatbed, dump bed, open-top, or freight box, by either crane or forklift, depending upon the loading capabilities of the manufacturer, for transportation. A crane would load each coil one behind another with their lengths aligned with the length of the trailer. When a forklift is used each coil is loaded one next to another from a longitudinal side of the trailer so that the coil length is oriented transversely to the length of the trailer. This latter positioning is referred to in the transportation industry as a "vertical" or "suicide" position due to the increased likelihood that a coil may start rolling along the direction of the trailer's travel due to generated inertial forces. Depending upon the length of the coils to be transported, they may be stacked one behind the other to fill the rack or racks as the case may be. The trailers used in transporting coils are usually also used for other transportation purposes. Therefore, the means employed to secure the coil to the flatbed are normally capable of being removed from the flatbed.
Heretofore, a coil of the type to which the present invention is directed would be placed on top of a removable set of two parallel wooden beams with square cross-section, such as 4 inch by 4 inch conventional wooden beams. The beams keep the coil off the ground or supporting surface and serve as two edges of contact with the coil. The coil should not touch the ground or support surface because that causes the coil to roll back and forth between the beams. Certain manufacturers require the beams to have a bevel along the top longitudinal edge facing the coil to prevent sharp edges from impacting against the coil and potentially damaging said coil. These parallel beams are held in their relative position using two cross members, usually flat strips of 1/4 inch thick galvanized steel, that extend underneath and perpendicularly to each parallel beam. At each end, these cross members are bent upwardly, then backwardly toward the opposite end, and finally downwardly, to form a generally D-shaped or triangularly shaped back stopper disposed on the outside of the beams to maintain their relative parallel position. These parts are not attached to one another, which assists in removal of the set-up.
Using this set-up, a coil is placed on top of and between the parallel beams atop the cross-members. The coil is then tied down to the trailer bed with chains and chain binders. These chains are typically placed laterally over the coil with the ends of the chains secured to the trailer and tension supplied to the chains through conventional chain binders. Additional chains may be placed longitudinally along the coil through its central core and tied to the trailer similarly.
The prior art as described above is conventional and well known in the industry and the field of art of the present invention. The applicant has found, as has the industry itself, that this securing system poses threats to the safety of workers and possibly other vehicles on the road.
It is important for security and safety to assure that a coil does not shift or roll in any manner during transportation. Once any slack occurs in the tension of the securing chains that might be caused by rolling or shifting of the coil during transport, the rack set-up may be potentially dangerous. This situation can cause the coil to further shift and/or roll, which will cause more deterioration of the set-up. Because the parts of the rack set-up are not securely attached to one another or to the flatbed support surface, the shifting of the parts can lead to eventual failure of the set-up causing the coil to essentially be without restraints. Under conditions of transportation of such a heavy object, the coil can obtain a devastating energy from inertia that can cause tremendous risks to life and property if the coil breaks free.
An additionional danger of this set-up is the back stoppers formed from the curved D-shaped portions of the cross-members that are susceptible and known to collapse or deform, either under static load from the coil or under dynamic loads caused by the shifting of the coil when it has become loose or by the jarring and shaking of the coil caused from undulations and imperfections in a road surface. Further, this type of set-up provides no provision for preventing the sliding of the coil in its length-wise direction.
Racks for securing cylindrically shaped objects are shown, for example, in U.S. Pat. Nos. 3,387,811; 4,013,256; 4,382,733; 5,067,871; 5,346,165; 5,441,220; and 5,607,133. However none of these racks are suitable for carrying cylindrically shaped objects or coils of the type intended for the present invention.